Inspecting a specific value from a specimen such as blood is generally carried out by way of measurement with testing papers, i.e. sensor strips (biosensor strips). For example, measuring blood glucose proceeds in the course as follows. First, a finger is inserted into a glucose monitor and then blood is taken from the finger. As this blood is automatically sucked into the inlet of a sensor strip when it arrives at the sensor strip pinned up the glucose monitor, a resultant glucose value is expressed on the screen of the monitor.
For the strip structure, a unit strip has been usually fabricated in the following manner. A plastic housing is formed of top and bottom plates. On the plastic housing are overlapped a nitrocellulose membrane, a hemolysis inhibition pad and a sampling pad in order. Then, after folding and inserting the top plate in a hole pin, it is joined by means of an electric iron to complete the structure. However, such an integrated strip structure is disadvantageous to production yield and consumes a large quantity of blood, mostly causing irregular variations on values of measurement due to compressive gaps between the top and bottom plates.
Meanwhile, there has been a multi strip with separated lop and bottom plates of the plastic housing, in which a nitrocellulose membrane and a hemolysis inhibition pad are laminated on a polypropylene plate (backing plate) having circular punches at an inspection point. On the laminated structure, sampling pads are layered on the plastic housing in order and the top plate is inserted to join therewith. Then, a sampling hole is formed to be wet with blood at once so as to measure three items of total cholesterol high-density lipoprotein (HDL) and triglyceride (TG). But, it could generate variations on values of measurement, depending upon points to which blood is dropping, in a large size of the sampling hole.